The present disclosure relates to an opening and closing mechanism for opening and closing a toner supply port of a toner guide by using an opening and closing member, and in particular, relates to a toner supply device and an image forming apparatus configured to prevent toner leaked from a toner supply port from pouring down from an opening and closing member when the opening and closing member is opened and closed.
A developing device is installed in an image forming apparatus, such as a copier or a printer, that forms an image on a print sheet by the electrophotography. Developer containing toner is stored in the developing device. The developing device develops an electrostatic latent image formed on an image carrying member such as a photoconductor drum, by the toner contained in the developer. As the developing is performed, the toner stored in the developing device is reduced. As a result, the image forming apparatus includes a toner container storing toner, and the toner is supplied from the toner container to the developing device. Conventionally, the image forming apparatus includes a toner supply device that supplies the toner from the toner container to the developing device. The toner supply device includes a toner guide that guides the toner to a predetermined position. The toner guide includes a toner supply port and an opening and closing member (shutter member). The toner is supplied to the developing device via the toner supply port. The opening and closing member opens and closes the toner supply port.
According to a conventional image forming apparatus, the developing device is attached, in a detachable manner, to a housing of the image forming apparatus so that the developing device can be replaced. In this type of image forming apparatus, an opening and closing member is moved from a closing position of closing the toner supply port to an opening position interlockingly with the attachment operation of the developing device to the housing. In addition, when the developing device is attached to the housing, a toner replenishing port of the developing device is positioned and aligned with the toner supply port. This allows the developing device to receive toner supplied from the toner supply port. In addition, the opening and closing member is biased by a spring or the like in a closing direction directed from the opening position to the closing position, and when the developing device is pulled out from the housing, the opening and closing member is moved to the closing position by the biasing force of the spring.